Fixed a negative number bug in the tokenizer; started work on a new calc_engine. Mostly working as of this commit.

tokenizer.py

@@ -27,13 +27,18 @@ def get_tokens_from_expression_string(expression_string):
 		
 		elif c == '-' and not parsing_number:
 			if expression_string[i + 1] == '.' or expression_string[i + 1].isdigit():
-				tmp = "-"
-				parsing_number = True
+				if  tokens[-1].type == token.TokenType.exp_end:
+					tokens.append(token.Token(c, token.TokenType.get_operator(c)))
+					parsing_number = False
+					tmp = ""
+				else:
+					tokens.append(token.Token('+', token.TokenType.add))
+					tmp = "-"
+					parsing_number = True
 			else:
 				tokens.append(token.Token(c, token.TokenType.get_operator(c)))
 				parsing_number = False
 				tmp = ""
-				continue
 		
 		elif c == '(':
 			if parsing_number:
@@ -44,7 +49,7 @@ def get_tokens_from_expression_string(expression_string):
 			tmp = ""
 			continue
 		elif c == ')':
-			if parsing_number:				
+			if parsing_number:	
 				tokens.append(token.Token(tmp, token.TokenType.constant))
 			tokens.append(token.Token(")", token.TokenType.exp_end))
 			parsing_number = False
@@ -102,5 +107,5 @@ def replace_variables(tokens, new_constants):
 	
 def print_token_list(tokens):
 	for tk in tokens:
-		print("%s" %(tk.value), end = "")#, token.TokenType.get_token_type_name(tk.type)), end = "")
+		print("%s " %(tk.value), end = "")#, token.TokenType.get_token_type_name(tk.type)), end = "")
 	print()